<template>
  <div class="el-tree-select">
    <el-select ref="treeSelect" v-model="valueId" style="width: 100%" :filterable="true" :clearable="true" :filter-method="selectFilterData" :placeholder="placeholder" @clear="clearHandle">
      <el-option :value="valueId" :label="valueTitle">
        <el-tree id="tree-option" ref="selectTree" :accordion="accordion" :data="options" :props="objMap" :node-key="objMap.value" :expand-on-click-node="false" :default-expanded-keys="defaultExpandedKey" :filter-node-method="filterNode" @nodeClick="handleNodeClick"></el-tree>
      </el-option>
    </el-select>
  </div>
</template>

<script setup lang="ts">
  import { getCurrentInstance, ComponentInternalInstance, computed, ref, onMounted, watch, nextTick } from "vue";

  const { proxy } = getCurrentInstance() as ComponentInternalInstance;

  const props = defineProps({
    /* 配置项 */
    objMap: {
      type: Object,
      default: () => {
        return {
          value: "id", // ID字段名
          label: "label", // 显示名称
          children: "children" // 子级字段名
        };
      }
    },
    /* 自动收起 */
    accordion: {
      type: Boolean,
      default: () => {
        return false;
      }
    },
    /**当前双向数据绑定的值 */
    value: {
      type: [String, Number],
      default: ""
    },
    /**当前的数据 */
    options: {
      type: Array,
      default: () => []
    },
    /**输入框内部的文字 */
    placeholder: {
      type: String,
      default: ""
    }
  });

  const emit = defineEmits(["update:value"]);

  const valueId = computed({
    get: () => props.value,
    set: (val) => {
      emit("update:value", val);
    }
  });
  const valueTitle = ref("");
  const defaultExpandedKey = ref<any[]>([]);

  function initHandle() {
    nextTick(() => {
      const selectedValue = valueId.value;
      if (selectedValue !== null && typeof selectedValue !== "undefined") {
        const node = (proxy?.$refs.selectTree as any).getNode(selectedValue);
        if (node) {
          valueTitle.value = node.data[props.objMap.label];
          (proxy?.$refs.selectTree as any).setCurrentKey(selectedValue); // 设置默认选中
          defaultExpandedKey.value = [selectedValue]; // 设置默认展开
        }
      } else {
        clearHandle();
      }
    });
  }
  function handleNodeClick(node: any) {
    valueTitle.value = node[props.objMap.label];
    valueId.value = node[props.objMap.value];
    defaultExpandedKey.value = [];
    (proxy?.$refs.treeSelect as any).blur();
    selectFilterData("");
  }
  function selectFilterData(val: any) {
    (proxy?.$refs.selectTree as any).filter(val);
  }
  function filterNode(value: any, data: any) {
    if (!value) return true;
    return data[props.objMap["label"]].indexOf(value) !== -1;
  }
  function clearHandle() {
    valueTitle.value = "";
    valueId.value = "";
    defaultExpandedKey.value = [];
    clearSelected();
  }
  function clearSelected() {
    const allNode = document.querySelectorAll("#tree-option .el-tree-node");
    allNode.forEach((element) => element.classList.remove("is-current"));
  }

  onMounted(() => {
    initHandle();
  });

  watch(valueId, () => {
    initHandle();
  });
</script>

<style lang="scss" scoped>
  @import "@/assets/styles/variables.module.scss";

  .el-scrollbar .el-scrollbar__view .el-select-dropdown__item {
    padding: 0;
    background-color: #fff;
    height: auto;
  }

  .el-select-dropdown__item.selected {
    font-weight: normal;
  }

  ul li .el-tree .el-tree-node__content {
    height: auto;
    padding: 0 20px;
    box-sizing: border-box;
  }

  :deep(.el-tree-node__content:hover),
  :deep(.el-tree-node__content:active),
  :deep(.is-current > div:first-child),
  :deep(.el-tree-node__content:focus) {
    background-color: mix(#fff, $--color-primary, 90%);
    color: $--color-primary;
  }
</style>
